1. Field of the Invention
The present invention relates to an ink cartridge and an ink supply device comprising a cartridge mounting portion to which the ink cartridge is configured to be mounted.
2. Description of Related Art
A known image recording apparatus, as described in Patent Application Publication No. JP 2009-132098 A, includes a tube-supply system which has an ink cartridge positioned outside of a carriage carrying a recording head. The ink cartridge and the recording head are connected via a flexible tube. The known image recording apparatus has a cartridge mounting portion having an opening at the front of the image recording apparatus, and the ink cartridge is configured to be mounted to the cartridge mounting portion via the opening in a horizontal direction. The cartridge mounting portion is configured to removably receive the ink cartridge. When the ink cartridge is mounted to the cartridge mounting portion, an ink path is formed between the ink cartridge and the recording head via the flexible tube. Ink is supplied from the ink cartridge to the recording head via the ink path.
A known technique for determining an ink amount stored in an ink cartridge by optical means is described in Patent Application Publication No. JP H05-332812 A and U.S. Pat. No. 6,012,795 A. For example, a image recording apparatus has an ink cartridge, and the ink cartridge has a wall in which a light-transmissive plate is provided. When the inner surface of the light-transmissive plate contacts ink stored in the ink cartridge, the light-transmissive plate allows light to pass therethrough to reach the ink. When the inner surface of the light-transmissive plate does not contact ink, light is reflected totally at the inner surface of the light-transmissive plate. By detecting whether light emitted from a light emitter is reflected totally at the light-transmissive plate, the ink amount stored in the ink cartridge is determined.
Another known image recording apparatus, as described in Patent Application Publication No. JP H08-043174 A, has an ink cartridge in which light-wave guiding path is provided. By detecting the intensity of light entering the light-wave guiding path from one end of the light-wave guiding path and exiting the light-wave path from the other end of the light-wave guiding path, the ink amount stored in the ink cartridge is determined.